Novel adhesives and tapes including same

ABSTRACT

Novel adhesives for preparing metal foil adhesive tapes meeting Underwriter Laboratories requirements for use with rigid fiberglass air ducts, which adhesive comprises a copolymer of: (1) at least one activated ester-containing vinyl monomer of Formula I (as defined hereinafter); (2) at least one ethylenically unsaturated carboxylic acid containing 3-5 carbon atoms; (3) at least one acrylic or methacrylic acid ester of a non-tertiary alcohol having 1-14 carbon atoms; and (4) at least one vinyl ester of a saturated carboxylic acid, said polymer being crosslinked with a crosslinking agent reactive with the carboxylic acid moiety through its reactive hydrogen atom; and adhesive tapes prepared therefrom.

This application is related to my application Ser. No. 019,832 (PF1040)filed Feb. 28, 1987, now abandoned.

BACKGROUND OF THE INVENTION

The present invention relates to novel adhesives and, more particularly,to novel adhesives which can be coated onto an aluminum backing materialto provide so-called foil tapes which meet the very severe UnderwriterLaboratories, Inc. (UL) 181A requirements and specifications for usewith rigid fiberglass air ducts.

Foil tapes, e.g. pressure-sensitive or heat-bonded aluminum tapes are ofcourse known in the art. It is also heretofore known to employ foiltapes for such purposes as closure systems for use with factory-made airducts and connectors. However, recently UL has imposed very severestandards for this usage. Consequently, the primary task of thisinvention can be said to develop a novel aluminum (foil) tape which willmeet the recent UL requirements and specifications, as detailedhereinafter, for the aforementioned usage.

    ______________________________________                                        U.L. SPECIFICATIONS                                                           ______________________________________                                        Test No.      Description                                                     ______________________________________                                                      Peel Adhesion                                                                 Three samples from                                                            each of three separate                                                        rolls of tape cut in 1                                                        inch (25.4 mm) wide by                                                        12 inches (305 mm) long                                                       strips are to be tested.                                                      The tape samples are to                                                       be applied (as specified                                                      in ASTM D-3330-83) to a                                                       stainless steel panel                                                         with a mechanically                                                           operated roller weighing 10                                                   pounds (4.53 kg.). The roller                                                 is to pass over each sample                                                   five times in each                                                            direction. The test                                                           load is to be applied 15                                                      minutes after completion                                                      of the rolling.                                                 1             The average peel adhesion                                                     strength of each roll of                                                      aluminum tape shall be ≧ 3.75                                          lbs. (60 oz) per inch of width                                                4 (0.66 N/mm) of tape, with no                                                individual sample having a                                                    value ≦ 3.20 lbs (51.2 oz) per                                         inch of width (0.56 N/mm).                                                    Shear Adhesion                                                                The shear adhesion                                                            strength of aluminum tape is                                                  to be determined in accordance                                                with ASTM D-3654-82, as                                                       modified in the following                                                     description. One sample from                                                  each of four separate rolls                                                   are to be tested. Samples                                                     are to be cut in 1-inch (25.4                                                 mm) wide by 6-inch (152 mm)                                                   long strips. The cut samples                                                  and specified stainless steel                                                 panels are to be maintained at                                                the specified application                                                     conditions a minimum of one                                                   hour prior to applying samples                                                to the panels. The tape is                                                    to be applied to the panel                                                    with a mechanically operated                                                  roller weighing 10 pounds-mass                                                (4.53 kg). The roller is to                                                   pass each sample five times                                                   in each direction. Using a                                                    cutting gig or razor blade,                                                   the rolled portion of                                                         the sample is to be trimmed to                                                a 1 inch by 1 inch square on                                                  the panel, such that the                                                      remaining test sample measures                                                1 inch by 5 inches. The tape                                                  is to be allowed to dwell on                                                  the panel for the specified                                                   time. After dwelling, the                                                     clamp is to be placed on the                                                  free end of the sample,                                                       insuring that the clamp                                                       extends completely across the                                                 width of the specimen and is                                                  aligned to uniformly                                                          distribute the load. The                                                      specified test load is then to                                                be applied to the clamp gently                                                so as not to cause any shear                                                  impact force on the sample.                                                   The load is to be applied for                                                 the specified test duration.                                                  The test panel is to be                                                       positioned at 2 degrees from                                                  the vertical so that the test                                                 substrate forms a 178° angle                                           with the extended tape sample.                                                Individual samples of the tape                                                are to be tested in accordance                                                with each of the conditions as                                                set forth hereinbelow:                                          ______________________________________                                            Application                                                                              Dwell     Test    Test                                             Condition  Time      Condition                                                                             Load   Duration                              ______________________________________                                        2.  40° F.                                                                            15 minutes                                                                              40° F.                                                                         5 lbs. 6 hours                                   (4.4° C.)             (22.2 N)                                         dry substrate                                                             3.  73.4° F.                                                                          15 minutes                                                                              73.4° F.                                                                       5 lbs. 6 hours                                   (23° C.)                                                               50% RH                                                                    4.  73.4° F.                                                                          24 hours  73.4° F.                                                                       10 lbs.                                                                              120 hours                                 (23° C.)                                                               50% RH                                                                    5.  73.4°  F.                                                                         15 minutes                                                                              150° F.                                                                        5 lbs. 6 hours                                   (23° C.)      (65.6° C.)                                        50% RH                                                                    ______________________________________                                    

The shear adhesion strength of the tape (in each of the above tests)shall be such that the tape is able to maintain the test loads specifiedin the tests for the indicated test durations without evidence ofseparation or slippage in excess of 1/32 inch (0.79 mm).

The aforementioned tests (peel adhesion and shear adhesion) constitutethe essential criteria which are critical to achieve in order to providean aluminum tape meeting UL specifications for use with air ducts andconnectors. However, for the sake of accuracy, it is to be noted thatthey are not the only tests which must be passed to satisfy ULspecifications. One such test is a tensile strength test for the tapebacking (foil). Another is peel adhesion at 20° angle. The former is notrelevant to this invention and the latter will be met if the adhesivepasses the five critical tests enumerated above.

Other UL criteria, specifically surface burning characteristics, moldgrowth and humidity tests, temperature/pressure cycling tests, burningtest and manufacturing and production tests, as detailed in UL181A, arenot difficult to meet and for purposes of a clear understanding of thenature and objects of this invention need not be described.

My aforementioned copending application, Ser. No. 019,832 (PF1040) isalso directed to the task of providing an adhesive which can be employedfor preparing metal foil adhesive tapes meeting UL specifications. Inthis copending application, the task is solved by providing an adhesivecomposition comprising a crosslinked copolymer of:

(1) at least one macromolecular monomer;

(2) at least one ethylenically unsaturated carboxylic acid containing3-5 carbon atoms;

(3) at least one acrylic or methacrylic acid ester of a non-tertiaryalcohol having 1-14 carbon atoms; and

(4) at least one vinyl ester of a saturated carboxylic acid;

the tetrapolymer being crosslinked with a crosslinking agent reactivewith said carboxylic acid moiety through its reactive hydrogen atom, themacromolecular monomer being a compound of the formula:

    R--Z--X

wherein R is lower alkyl, Z is a repeating monomeric unit selected fromthe group consisting of styrene, alpha(methylstyrene), isoprene,butadiene and mixtures thereof; n is a positive integer such thatmolecular weight is in the range from about 5,000 to about 50,000 and xis a polymerizable end group selected from the group consisting of:##STR1## where n' is a positive integer from 1-4 and R' is alkyl having1-4 carbon atoms.

The only commercially available macromolecular monomer of thisdescription and hence of necessity the preferred one is2-polystyrylethyl methacrylate which has been sold by Sartomer Company,a subsidiary of Atlantic Richfield under the name Chemlink ® 4500Macromer ™ Monomer.

However, subsequent to the invention described and claimed in theaforementioned copending application, Applicant and his assignee, TheKendall Company, was advised that the Chemlink ® Macromer would nolonger be commercially available to them.

The task of the present invention can accordingly be described as beingto prepare a metal foil tape meeting UL requirements which is notnecessarily better than the invention in the earlier copendingapplication, but which utilized readily obtainable starting materials.

BRIEF DESCRIPTION OF THE INVENTION

In accordance with the present invention, this task is solved byemploying, in lieu of the aforementioned macromolecular monomers, asactivated ester-containing vinyl monomer of the formula: ##STR2##wherein R is hydrogen or methyl; and each R', which may be the same ordifferent, is alkyl having 1-6 carbon atoms, cycloalkyl having 5-6carbon atoms, or a 2-hydroxyalkyl having 2-6 carbon atoms.

The novel adhesives of this invention will comprise a copolymer of:

(1) at least one monomer of Formula (I);

(2) at least one ethylenically unsaturated carboxylic acid containing3-5 carbon atoms;

(3) at least one acrylic or methacrylic acid ester of a non-tertiaryalcohol having 1-14 carbon atoms; and

(4) at least one vinyl ester of a saturated carboxylic acid; and thenadmixing with the thus formed polymer of a crosslinking agent reactivewith the carboxylic acid moiety through its reactive hydrogen atom.

DETAILED DESCRIPTION OF THE INVENTION

As preciously mentioned, the present invention is directed to metal foiltapes meeting UL181A specifications for use with rigid fiberglass airducts, which tapes comprise a metal foil backing carrying a noveladhesive which is a copolymer of:

(1) at least one activated ester-containing vinyl monomer of Formula I;

(2) at least one ethylenically unsaturated carboxylic acid containing3-5 carbon atoms;

(3) at least one acrylic or methacrylic acid ester of a non-tertiaryalcohol having 1-14 carbon atoms; and

(4) at least one vinyl ester of a saturated carboxylic acid, saidpolymer being crosslinked with a crosslinking agent reactive with thecarboxylic acid moiety through its reactive hydrogen atom.

Useful monomers of Formula I include methyl acrylamidoglycolate methylether (MAGME), ethyl acrylamidoglycolate ethyl ether, butylacrylamidoglycolate butyl ether, methyl acrylamidoglycolate ethyl ether,and ethyl acrylamidoglycolate methyl ether.

The monomers of Formula I, including the aforementioned illustrativespecies, are known in the art and are described, for example, in U.S.Pat. No. 4,521,563 issued to Howard R. Lucas and assigned to AmericanCyanamid Company.

A preferred monomer of this description is: ##STR3## a white solid,melting point 70-73 ° C., available commercially in 95-97% purity fromAmerican Cyanamid Co. A preferred method of preparing MAGME is disclosedin U.S. Pat. No. 4,443,623 issued to James M. Photis and assigned toAmerican Cyanamid Company.

As examples of useful ethylenically unsaturated carboxylic acidscontaining 3-5 carbon atoms, mention may be made of acrylic acid,methacrylic acid, itaconic acid, maleic acid and fumaric acid, acrylicacid being particularly preferred.

Useful acrylic or methacrylic acid esters of non-tertiary alcoholshaving 1-14 carbon atoms include those previously mentioned withreference to U.S. Pat. No. 4,554,324, i.e. 1-butanol, 1-pentanol,2-pentanol, 3-pentanol, 2-methyl-1-butanol, 1-methyl-1-butanol,1-methyl-1-pentanol, 2-methyl-1-pentanol, 3-methyl-1-pentanol,2-ethyl-1-butanol, 3,5,5-trimethyl-1-hexanol,3-heptano1,2-octanol,l-decanol, 1-dodecanol as well as others. Preferredare acrylic acid esters of non-tertiary alcohols having 4-14 carbonatoms, e.g. butyl acrylate, amyl acrylate, decyl acrylate, laurylacrylate, and the like, 2-ethylhexyl acrylate being particularlypreferred.

Suitable vinyl esters are those wherein the acid contains 1-6 carbonatoms, e.g. vinyl acetate, vinyl propionate, vinyl butyrate, vinylvalerate, etc., vinyl acetate being particularly preferred.

Suitable crosslinking agents, i.e. crosslinkers reactive with thecarboxylic acid moiety through its reactive hydrogen atom are per seknown in the art and its selection will be within the expected judgmentof the skilled worker in the light of the present disclosure.

Such per se known crosslinkers include aluminum acetylacetonate andalkylated amino crosslinkers of the "CYMEL" or "BEETLE" (Trademarks ofAmerican Cyanamide Co.) Series, highly alkylated melamines such as"CYMEL" 303 (understood to be hexamethoxymethyl melamine) being aparticularly efficient one. Others may be readily suggested to thoseskilled in the art.

An important aspect of the present invention is the discovery thatcrosslinking in the described manner markedly increases the shearadhesion with a slighter "trade" or drop-off in peel adhesion.Accordingly, the non-crosslinked polymer should have sufficient initialadhesion to allow for a slight drop-off and still possess sufficientpeel adhesion to meet UL specifications. Since the peel adhesioncriteria is not as difficult to achieve as the shear adhesion,particularly shear adhesion meeting high temperature and long termcriteria, this is not a significant problem in the selection of themonomers for copolymerization.

Nevertheless, because of this slight drop-off and further in view ofvarying efficiencies of selected crosslinking agents, it is not possibleto state quantitatively the weight ratio of crosslinker which should beemployed in the practice of this invention.

Functionally, it can be stated and will be understood that sufficientcrosslinker should be employed to increase the shear adhesion toacceptable levels while at the same time not lowering the peel adhesionform initially acceptable levels to levels which are no longeracceptable.

By way of illustration, when employing aluminum acetylacetonate or CYMEL303, levels on the order of 0.1 to 1.0 parts per 100 parts by weight ofpolymer are entirely acceptable.

The copolymers of this invention may be prepared by routine chemicalsynthesis within the expected judgment of those skilled in the art.Specifically, the monomeric components may be admixed and polymerizationeffected in the presence of the usual polymerization initiators, chainextenders, etc. The resulting copolymer (which may be regarded as anintermediate in the synthesis of the ultimate chemically crosslinkedpolymers of this invention) is then admixed with per se knowncrosslinkers for the carboxylic acid monomeric components, as heretoforediscussed, to provided the desired polymeric adhesive. Sufficientcrosslinking will occur during manufacture, e.g. solvent removal, tomake the adhesive operative for meeting UL specifications. However, ithas been determined that further crosslinking will occur over a periodof time, particularly during shelf life at elevated temperatures.

By way of recapitulation, the novel adhesives of this invention meetingUL181A specifications for foil tapes for use with rigid fiberglass airducts consist essentially of:

(1) at least one ester-containing vinyl monomer of Formula I;

(2) at least one ethylenically unsaturated carboxylic acid containing3-5 carbon atoms;

(3) at least one acrylic or methacrylic acid ester of a non-tertiaryalcohol having 1-14 carbon atoms; and

(4) at least one vinyl ester of a saturated carboxylic acid,

the polymer being crosslinked with a crosslinking agent reactive withthe carboxylic acid moiety through its reactive hydrogen atom.

Critical to this invention is that foil tapes carrying a layer of thisadhesive meet the aforementioned UL181A criteria. It follows a fortiorithat the particular monomer employed, their amounts and the degree ofcrosslinking must all be selected so that the resulting crosslinkedpolymeric adhesive will meet UL181A criteria.

This will be treated as a critical limitation in the appended claims.Since it is not feasible to prepare and test all polymers within theabove definition, it is to be expressly understood that those polymerswhich satisfy this condition are within the scope of the appended claimsand, conversely, any adhesives which do not are not contemplated by thisinvention and accordingly are not within the scope of the appendedclaims.

In this context, with respect to amounts of the individual monomerswhich may be employed, the following ranges have been found operative:

(1) from about 5 to about 20 parts by weight of a monomer or mixture ofmonomers of Formula I;

(2) from about 3 to about 10 parts by weight of ethylenicallyunsaturated carboxylic acid;

(3) from about 70 to about 85 parts by weight of acrylic or methacrylicacid ester of a non-tertiary alcohol having 1-14 carbon atoms; and

(4) from about 7 to about 22 parts by weight of vinyl ester of asaturated carboxylic acid.

However, it is envisioned that other ratios of particular monomers maypossibly be employed to satisfy UL181A specifications.

Illustrative polymers which may be prepared for crosslinking inaccordance with the practice of this invention to provide foil tapesmeeting UL181A specifications are set forth in the following table.

                                      TABLE 1                                     __________________________________________________________________________       2-ETHYHEXYL                                                                NO.                                                                              ACRYLATE MAGME ACRYLIC ACID                                                                           VINYL ACETATE                                                                           HYDROXYETHYL ACRYLATE                    __________________________________________________________________________    1. 73.6     9.0   6.4      11.0      --                                       2. 75.6     7.0   6.4      11.0      --                                       3. 72.0     9.0   8.0      11.0      --                                       4. 71.0     9.0   8.0      12.0      --                                       5. 70.0     9.0   8.0      12.0      1.0                                      6. 72.0     9.0   8.0      10.0      1.0                                      7. 72.0     9.0   8.0      10.0      1.0                                      8. 70.0     9.0   8.0      11.5      1.5                                      9. 72.5     4.5   8.0      12.0      3.0                                      10.                                                                              71.0     4.5   8.0      12.0      4.5                                         71.0     3.0   8.0      12.0      6.0                                      __________________________________________________________________________

The polymers listed in Table 1 may be crosslinked with a suitablecrosslinker for the acrylic acid moiety as heretofore described, e.g.aluminum acetylacetonate or CYMEL 303.

It should be noted, however, that although accelerating aging criteriaare not a requirement of UL181A, they are nevertheless very useful froma manufacturing standpoint as a benchmark for determining shelf lifestability of a product. Accelerating aging studies indicate that thepolymers containing hydroxyethyl acrylate have reduced shelf life.Consequently, absent the incorporation of a stabilizing system, polymerscontaining this monomer would not appear to be good candidates from acommercial standpoint, due to reduced shelf life.

The following examples show by way of illustration and not by way oflimitation the practice of this invention.

EXAMPLE 1

The polymerization was carried out in a glass reaction kettle equippedwith a reflux condenser, mechanical stirrer and two graduated droppingfunnels attached to metering pumps. To the reaction kettle was placedabout 9.135 parts by weight of 2-ethylhexyl acrylate, 1.116 parts ofMAGME, 0.792 parts of acrylic acid and 1.366 parts of vinyl acetate(approximately 25% of the monomer mixture), along with 0.779 parts oftoluene (as molecular weight regulator or chain transfer agent), 0.111parts of "Lupersol PMS" (trademark of Pennwalt Corporation for apolymerization initiator, 1-butyperoxy-2-ethylhexanoate) and 15.851parts of ethyl acetate (solvent). The reaction kettle was purged withnitrogen and heated at 75° C. (+2° C.) for about one hour. The remaining75% of the monomer mix, namely 27.406 parts of 2-ethylhexyl acrylate,3.347 parts of MAGME, 2.378 parts of acrylic acid and 4.098 parts ofvinyl acetate were meanwhile added to 24.471 parts of ethyl acetate andpremixed to a homogenous state. This premix was added to the reactionkettle over a period of about 13/4 hours. Simultaneously, 0.222 parts ofazobisisobutyronitrile (initiator) in 7.647 parts of ethylacetate wereadded at a constant rate over a period of about 11/4 hour. The monomerand initiator additions were at a sufficient rate to raise the reactiontemperature exceeding 75° C. after about 30 minutes. An exothermicreaction resulted with the maximum temperature exceeding 75° C., thusrequiring external cooling. After maintaining the temperature around 75°for one hour, 0.028 additional parts of azobisisobutyronitrile in 1.251parts of ethyl acetate were added. The reaction mixture was thenmaintained at about 75° C. for an additional two hours and then cooledto room temperature to yield the tetrapolymer of Formula I (in Table I),in the following approximate proportions: 73.6 2-ethylhexyl acrylate/9.0MAGME/6.4 acrylic acid/11.0 vinyl acetate (96-99% monomer conversion),molecular weight=270,000-325,000; Mn=46,000-73,000; MWD=5.5-7.0.

EXAMPLES 2-11

In a similar manner, the copolymers of Formulae 2-11 were prepared.

EXAMPLE 12

0.5 parts of aluminum acetylacetonate per 100 parts by weight of polymerwere added to the reaction mixture of Example 1 followed by stirringwith a mechanical stirrer at room temperature to provide the crosslinkedpolymeric adhesive.

EXAMPLES 13-16

In a similar manner, Formulae 2-5, selected as model candidates, werecrosslinked with varying amounts of CYMEL 303 or aluminumacetylacetonate, as detailed hereinafter in Table 2.

Aluminum foil tapes were prepared from each of the crosslinked adhesivesof Example 12-16, i.e the crosslinked copolymers of formulae 12-16. Inaddition, aluminum tapes were prepared from certain of thenon-crosslinked copolymers to serve as controls. In each instance theadhesive was cast onto the backing material at a thickness of about 1.5mils.

With respect to the thickness of the adhesive, it is to be noted thatthe present invention permits the use of significantly thinner adhesivecoatings than those employed in the practice of the invention describedand claimed in the aforementioned copending application, Ser. No.019,832, (PF1040). For instance, in the illustrative examples in thecopending application, thicknesses on the order of 2.3-2.5 mils wereemployed a compared with the 1.5 mils in the instant illustrativeexamples, a reduction in thickness of about 35-40% resulting in asignificant cost saving in the manufacture along with a correspondingreduction in diameter and weight of a roll of tape of a given length.

With the exception of Formula 1, each of the resulting foil tapes wassubmitted to UL181A tests 1, 4 and 5 as previously described in detail.Tests 2 and 3 were not performed simply as a matter of expediency sincethey are not necessary for purposes of evaluation.

In this context, it is well understood in the art that Shear Tests 4(long term) and 5 (high temperature) are the most critical and that ifan adhesive tape passes these tests, it will easily pass shear test 2and 3, as well. Of course, the converse is not true so that passage oftests 2 and 3 does not imply passage of 4 and 5.

Since increasing the shear adhesion in accordance with this inventiontypically results in some lowering of the peel adhesion, as previouslydiscussed, it is still most advisable, if not essential, also to performPeel Adhesion Test 1, to assure acceptability of the model candidate.

In any event, Applicant can state unequivocally, based upon hisknowledge of testing adhesives in general and specifically in view ofhis observation in the aforementioned related application Ser. No.019,832, (PF1040) that Tests 2 and 3 can in fact be eliminated toexpedite ascertainment of whether or not a particular candidate meetsUL181A specifications.

The results of these tests are set forth in Table 2.

                                      TABLE 2                                     __________________________________________________________________________                                 TEST 2                                                                              TEST 3 TEST 4                                                                               TEST                         UL181A Specifications   TEST 1                                                                             SHEAR SHEAR  SHEAR SHEAR                         TEST COPOLYMERS         PEEL (low temp.)                                                                         (short term)                                                                         (long term)                                                                         (high temp.)                  FORMULA NO.    *MEL                                                                              **AAA                                                                              >60 oz.                                                                            >6 hrs.                                                                             >6 hrs.                                                                              >120 hrs.                                                                           >6 hrs.                       __________________________________________________________________________    1              --  --   80.0              110.0 2.4                           1                  0.5  75.0 >200  >200   >120  >200                          1                  0.3  80.6 >200  >200   >150  >143                          2                  0.3  66.5              >300  20.0                          3              --  --   68.4              >260  5.9                           4              --  --   84.5              >312  2.62                          4              0.5      80.9              >144  >100                          4              --  0.1  74.2              >120  >145                          5              --  --   89.0              >260  7.3                           5              1.0      79.0              >200  >100                          5              0.5      80.0              >176  >120                          5              0.75     74.2              >120  >145                          __________________________________________________________________________

In the above Table, the "greater than" (>) sign means that the test wasstopped after the indicated passage of time. It accordingly does notimply that the recited figures are the upper limits before failure. Theremaining data indicate the time at which failure occurred.

As mentioned earlier, the copolymer of Formula 1, crosslinked with 0.5and 0.3 parts of crosslinker (as shown in Table 2) was, in eachinstance, submitted to the low temperature and short term Shear AdhesionTests 2 and 3. In each instance, no failure way evidenced after 200hours when the tests were terminated.

Since certain changes may be made without departing from the scope ofthe invention herein described, it is intended that all matter containedin the foregoing description, including the examples, shall be taken asillustrative and not in a limiting sense.

What is claimed is:
 1. A metal foil tape meeting UnderwritersLaboratories criteria for use with rigid fiberglass air ducts, said tapecomprising a metal foil backing sheet carrying a layer of an adhesivecomposition comprising a crosslinked copolymer of:(1) an activatedester-containing vinyl monomer of the formula: ##STR4## wherein R ishydrogen or methyl; and R' is alkyl having one to six carbon atoms, or2-hydroxyalkyl having two to six carbon atoms; (2) at least oneethylenically unsaturated carboxylic acid containing 3-5 carbon atoms;(3) at least one acrylic or methacrylic acid ester of a non-tertiaryalcohol having 1-14 carbon atoms; and (4) at least one vinyl ester of asaturated carboxylic acid.
 2. A metal foil tape as defined in claim 1wherein said vinyl monomer is methyl acrylamidoglycolate ethyl ether. 3.A metal foil tape as defined in claim 1 wherein said ethylenicallyunsaturated carboxylic acid is selected from the group consisting ofacrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaricacid./
 4. A metal foil tape as defined in claim 1 wherein saidnon-tertiary alcohol is selected from the group consisting of 1-butanol,1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol,1-methyl-1-butanol, 1-methyl-1-pentanol, 2-methyl-1-pentanol,3-methyl-1-pentanol, 2-ethyl-1-butanol, 2-ethyl-1-hexanol,3,5,5-trimethyl-1-hexanol, 3-heptano,2-octanol,1-decanol and1-dodecanol.
 5. A metal foil tape as defined in claim 1 wherein saidvinyl ester is selected from the group consisting of vinyl acetate,vinyl propionate, vinyl butyrate and vinyl valerate.
 6. A metal foiltape as defined in claim 1 wherein said copolymer is crosslinked with amelamine resin or aluminum acetylacetonate crosslinking agent.
 7. Ametal foil tape meeting Underwriter Laboratories criteria for use withrigid fiberglass air ducts, said tape comprising a metal foil backingsheet carrying a layer of an adhesive composition comprising acrosslinked copolymer of:(1) from about 3 to about 20 parts by weight ofan activated ester-containing vinyl monomer of the formula: ##STR5##wherein R is hydrogen or methyl; and R' is alkyl having one to sixcarbon atoms, or 2-hydroxyalkyl having two to six carbon atoms; (2) fromabout 3 to about 10 parts by weight of at least one ethylenicallyunsaturated carboxylic acid selected from the group consisting ofacrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaricacid; (3) from about 70 to about 85 parts by weight of at least oneacrylic or methacrylic acid ester of a non-tertiary alcohol having 1 to14 carbon atoms selected from the group consisting of 1-butanol,1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol,2-ethyl-1-hexanol, 1-methyl-1-butanol, 1-methyl-1-pentanol,2-methyl-1-pentanol, 3-methyl-1-pentanol, 2-ethyl-1-butanol,3,5,5-trimethyl-1-hexanol, 3-heptanol,2-octanol,1-decanol and1-dodecanol; and (4) from about 7 to about 22 parts by weight of atleast one vinyl ester of a saturated carboxylic acid selected from thegroup consisting of vinyl acetate, vinyl propionate, vinyl butyrate andvinyl valerate; said copolymer being crosslinked with a crosslinkingagent reactive with said carboxylic acid moiety through its are reactivehydrogen atom.
 8. A metal foil tape as defined in claim 7 wherein saidvinyl monomer is methyl acrylamidoglycolate ethyl ether.
 9. A metal foiltape as defined in claim 8 wherein said carboxylic acid is acrylic acid.10. A metal foil tape as defined in claim 9 wherein said acrylic acid ormethacrylic acid ester is 2-ethylhexyl acrylate.
 11. A metal foil tapeas defined in claim 10 wherein said vinyl ester is vinyl acetate.
 12. Anadhesive tape comprising a backing sheet material carrying a layer of anadhesive composition adapted for meeting Underwriters Laboratoriesspecifications for metal foil adhesive tapes for use with rigidfiberglass air ducts, said composition comprising a copolymer of:(1) anactivated ester-containing vinyl monomer of the formula: ##STR6##wherein R is hydrogen or methyl; and R' is alkyl having one to sixcarbon atoms, or 2-hydroxyalkyl having two to six carbon atoms; (2) atleast one ethylenically unsaturated carboxylic acid containing 3-5carbon atoms; (3) at least one acrylic or methacrylic acid ester of anon-tertiary alcohol having 1-14 carbon atoms and; (4) at least onevinyl ester of a saturated carboxylic acid; said polymer beingcrosslinked with a crosslinking agent reactive with the carboxylic acidmoiety through its reactive hydrogen atom.
 13. An adhesive tapecomprising a backing sheet material carrying a layer of an adhesivecomposition adapted for meeting Underwriters Laboratories specificationsfor metal foil adhesive tapes for use with rigid fiberglass air ducts,said composition comprising a copolymer of:(1) from about 3 to about 20parts by weight of an activated ester-containing vinyl monomer of theformula: ##STR7## wherein R is hydrogen or methyl; and R' is alkylhaving one to six carbon atoms, or 2-hydroalkyl having two to six carbonatoms; (2) from about 3 to about 10 parts by weight of at least oneethylenically unsaturated carboxylic acid selected from the groupconsisting of acrylic acid, methacrylic acid, itaconic acid, maleic acidand fumaric acid; (3) from about 70 to about 85 by weight of at least onacrylic or methacrylic acid ester of a non-tertiary alcohol having 1 to14 carbon atoms selected from the group consisting of 1-butanol,1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol,2-ethyl-1-hexanol, 1-methyl-1-pentanol, 3-methyl-1pentanol,2-ethyl-1-butanol, 3,5,5-trimethyl-1-hexanol, 3-heptanol, 2-octanol,1-decanol and 1-dodecanol; and (4) from about 7 to about 22 parts byweight of at least one vinyl ester of a saturated carboxylic acidselected from the group consisting of vinyl acetate, vinyl propionate,vinyl butyrate and vinyl valerate; said copolymer being crosslinked witha crosslinking agent reactive with said carboxylic acid moiety throughits are reactive hydrogen atom.